We are looking at hosting 3 globally distributed SQL Server installations at different data centers. The intent is that Site A will serve web traffic and data for a specific region, same with Site B ...

We have already Samba4 AD DC which is installed via git from sources (to Fedora), and it will work fine.
Now I should add there a secondary DC to domain, but I would like to use (CentOS 6.5) distro ...